HTC is running a promotion that will give you an extra $100 back when you trade in your old phone for an HTC smartphone on most major US carriers. Here are the details:

Starting November 27th, anyone looking to upgrade their eligible smartphone will have the opportunity to get an extra $100 back from HTC with the purchase of a new HTC Tilt 2, HTC Touch Pro2, HTC Imagio, or HTC Ozone.

The way it works is simple. Once the new phone is purchased, the customer can go to the appropriate site below and enter their specific promotional code. This will provide them with a mailing label, which they use to send their old smartphone, a copy of the UPC code from the new phone, and a copy of the invoice from the new phone. After that, they get a $100 check in the mail!